Father of Invention : Shopkeeper-Scientist Specializes in Gizmos, Gross-Outs and Keeping Creativity Alive

He is not the Dr. Kevorkian of Burbank, however. Mr. Wizard is more like it.

Ira Katz, 81, is the owner of Tri-Ess Sciences, a company that has been providing hobbyists, schools, magicians and the movie industry with supplies for 46 years. Budding scientists have been known to drool over his mail-order catalog, which is full of kits, chemistry sets, skeletons, bottled bodies of small animals for dissection, anatomy charts and a wide variety of laboratory equipment, from professional microscopes to single test tubes.

Katz doesn't just sell the stuff--he also makes use of it.

Through a door in the back of his shop is his well-stocked laboratory, where he invented numerous gizmos and special effects such as the richly colored smoke now commonly used in films and music videos. Taped to one shop wall, near thank-you letters from students he has helped with science projects, is a picture of Cher singing against a backdrop of his purple smoke.

In a high-tech era when most scientific research is a group effort requiring contributions from a host of specialists and data-crunching computers, Katz is one of the last in a long line of inventors who worked wonders in back rooms, basements and garages, letting their curiosity and creativity lead them into whatever endeavor might strike their fancy.

"Let me show you something," said Katz, addressing a visitor. It's probably the most oft-repeated sentence he utters.

With a sly smile, he led the way into his lab. Pulling out a small pocket knife, he asked his visitor to bare a wrist.

"The movie people love this one," he said, reaching for a couple of unmarked chemical bottles. Using a Q-tip, he painted a line of one potion across his intended victim's wrist. Then he covered the blade of the knife with the other. Both solutions were clear, leaving no trace.

"Imagine you are coming around a corner on a dark night and I jump out at you," said Katz, suddenly running the dull blade across the wrist.

Instantly, the chemicals react to make an absolutely convincing line of simulated blood. It would not take much acting to pretend the wrist had just been slashed.

"I call it 'A-B blood' because it takes two chemicals to make the effect," said Katz. With gusto, he described its use in a recent movie in which a woman scratched deep cuts into a man's face with her fingernails.

But the product is not limited to secular use. Katz also gets orders for "A-B blood" from fundamentalist church groups.

"They use it for their reenactment of the flagellation of Christ," he said. "Sells very well around Easter."

An assistant came to summon Katz to the shop, where a man was seeking advice on floor-polishing compounds. Meanwhile, Katz's daughter, Kim Greenfield, offered a tour of the store.

On industrial shelves and in glass display cases were stacks of products that could be purchased by customers who visit the mostly unadorned shop. There were some novelty items, such as ChemSlime, a "slippery, slimy" substance the store stocks for inexpensive holiday gifts. But most of the products have at least some serious intent.

"We try to find things that are based in science," said Greenfield, 40, vice president of Tri-Ess. "We don't want to load up on magic kits and things like that."

For younger students, there were kits designed to demonstrate the principles of solar energy, crystal formation, electric motors, weather forecasting, magnetism and telescopes. For the older set, there were genuine science lab tools, such as electronic balances, flasks, hydrometers and forceps.

On one shelf were samples of animal specimens for dissection and animal parts floating in a preservative. Whole bullfrogs were priced at $11.10 apiece, a fetal pig was going for $9.60 and a sheep's eye was only $1.

Lab chemicals are a specialty of Tri-Ess, but there were only a few children's chemistry sets for sale.

"Most of the sets on the market aren't worth having," Greenfield said. "They show how to make an effect, but they don't explain why it works. It's just hocus-pocus; it has nothing to do with scientific principles."

Instead, Tri-Ess packs its own, plain-wrap chemistry kits, meant to be used in experiments explained in a long-out-of-print basic chemistry book. Katz tried to get permission from the original publisher to reprint the book, but when negotiations fell through, Greenfield said, she and her father simply waited for the copyright to expire. Now they sell photocopies.

But he worries about the state of science education today, concerned that students are not learning the basics the way students did years ago.

"Nowadays kids in schools use calculators. What happens if the calculator breaks down? They can't add up a column of numbers."

The tour ended in Katz's office. "This is the last place you look for him," Greenfield said.